text: mod=10**9+7
  n,m=map(int,input().split())
  l=[]
  for i in range(n):
      l.append(input())
  ans=1
  for j in range(m):
      s=set()
      for i in range(n):
          s.add(l[i][j])
      ans=(ans*len(s))%mod
  print(ans%mod)